GAIN reference file

REFTYPE:

GAIN

Data model:

GainRefModel

The GAIN reference file contains a pixel-by-pixel gain map, which can be used to convert pixel values from units of DN to electrons. The gain values are assumed to be in units of e/DN.

Reference Selection Keywords for GAIN

CRDS selects appropriate GAIN references based on the following keywords. GAIN is not applicable for instruments not in the table. All keywords used for file selection are required.

Instrument	Keywords
WFI	instrument, detector, date, time

Standard ASDF metadata

The following table lists the attributes that are required to be present in all reference files. The first column shows the attribute in the ASDF reference file headers, which is the same as the name within the data model meta tree (second column). The second column gives the roman data model name for each attribute, which is useful when using data models in creating and populating a new reference file.

Attribute	Fully Qualified Path
author	model.meta.author
model_type	model.meta.model_type
date	model.meta.date
description	model.meta.description
instrument	model.meta.instrument.name
reftype	model.meta.reftype
telescope	model.meta.telescope
useafter	model.meta.useafter

NOTE: More information on standard required attributes can be found here: Standard ASDF metadata

Type Specific Keyword Attributes for GAIN

In addition to the standard reference file keyword attributes listed above, the following keyword attributess are required in GAIN reference files, because they are used as CRDS selectors (see Reference Selection Keywords for GAIN):

Keyword Attr.	Fully qualified path	Instruments
detector	model.meta.wfi_mode.detector	WFI

Reference File Format

GAIN reference files are asdf files with a single data array.

Data	Array Type	Dimensions	Data type
data	NDArray	4096 x 4096	float32

The ASDF file contains a single data arrays.